Atrial masses post cardiac transplantation: diagnostic and treatment dilemmas

Rapid Growth of Left Atrial Thrombus in a Pediatric Heart Transplant Recipient

We report on a 10-year-old female who rapidly developed a left atrial (LA) mass two months after orthotopic heart transplant. Nine days prior to detection of the mass, she received high-dose corticosteroids for acute cellular rejection (grade 2). Despite negative echocardiogram five days prior to detection, a large echogenic mass was noted in the LA (18 x 12 x 24 mm); it was surgically resected after unsuccessful anticoagulation treatment. Pathogenesis of this LA thrombus remains uncertain, but immunosuppression, acute rejection, and high-dose steroid therapy may have contributed. Surgical thrombectomy is a safe and effective treatment option for LA thrombus.

Giant Left Atrium Associated with Massive Thrombus Formation 14 Years after Orthotopic Heart Transplantation

We report the case of a 60-year-old patient who underwent orthotopic heart transplant 14 years earlier. Routine echocardiography showed giant masses in the left atrium. There were no symptoms or thromboembolic events in the past. Magnetic resonance imaging study revealed very enlarged left atrium (8.7 × 10.6 cm) occupied by irregular smooth mass (7 × 5 × 6.1 cm) with a stalk that was attached to the posterior left atrial wall in the area of graft suture lines. Intraoperative examination revealed a massive thrombus (12 × 10 cm) that filled almost the entire left atrial area.

Role of Imaging for Suspected Cardiac Thrombus

PURPOSE OF REVIEW

Cardiac thrombus formation is a frequent complication of a variety of prevalent diseases. Embolism of cardiac thrombus has the potential to result in significant morbidity and mortality from cerebrovascular and peripheral vascular events.

RECENT FINDINGS

Echocardiography is the most commonly used imaging modality for diagnosing intracardiac thrombus. However, technological advances in computed tomography and magnetic resonance imaging have allowed newer noninvasive modalities to evolve into robust tools for the clinical evaluation of patients suspected of disease. Complimentary use of these imaging techniques is crucial in the diagnosis of cardiac thrombus and initiation of anticoagulation therapy.

Expecting the unexpected: right atrial mass in a transplant patient

We present a 71‐year‐old male, who had had a heart transplantation 24 years prior, who came to our clinic with a low‐grade fever and a new II/VI holosystolic murmur. Echocardiography showed a large mass in the right atrium with attachment near the junction of the right atrium and superior vena cava. The patient was taken to the operating room for resection of the mass. Microscopic evaluation was consistent with thrombus. Differential diagnosis of cardiac masses after cardiac transplant includes tumour, thrombus, and vegetation. Final diagnosis can be challenging; multimodality imaging and biopsy or resection often are required for final diagnosis.

HLA-DRB1 typing by micro-bead array assay identifies the origin of early lymphoproliferative disorder in a heart transplant recipient

We report the case of a 68-year-old woman who underwent heart transplantation for hypertrophic cardiomyopathy. Two months after the transplant she developed mild fever and dyspnea with a marked drop in left ventricle ejection fraction of 31%. Coronary angiography was negative for cardiac allograft vasculopathy. Endomyocardial biopsy revealed ischemic damage with no evidence of acute cellular rejection, antibody-mediated rejection or viral myocarditis. A neoplastic process was suspected even though full-body computerized tomography was negative for malignancy. The patient died 4 months after transplantation. The autopsy showed acute antero-septal myocardial infarction due to a nodular epicardial EBV-related posttransplant lymphoproliferative disorder (PTLD) infiltrating the left anterior descending coronary artery with occlusive neoplastic thrombosis. We highlight two major aspects of this case: (1) the unusual occurrence of early PTLD involving the cardiac allograft and causing a fatal outcome, (2) the application of an immunological technique for HLA-DRB1 typing to posttransplant paraffin-embedded autopsy material to identify the recipient origin of this early malignancy, thus excluding a possible donor-transmitted neoplasm.